feat: document_preamble lint rule

[adthrasher]

This pull request adds a new rule to wdl.

• Rule Name: document_preamble
• Rule Kind: Lint warning
• Rule Code: v1::W009
• Packages: wdl-grammar

Implements document_preamble as defined in #11.

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• Your code builds clean without any errors or warnings.
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  ["keep a changelog"] for more information).
• Your commit messages follow the [conventional commit] style.
• Your changes are squashed into a single commit (unless there is a really
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Rule specific checks:

• You have added the rule as an entry within the the package-specific rule
  tables (wdl-ast/src/v1.rs for AST-based rules and
  wdl-grammar/src/v1.rs for parse tree-based rules).
• You have added the rule as an entry within the the global rule
  table at RULES.md.
• You have added the rule to the appropriate fn rules().
  • Validation rules added to wdl-ast should be added to fn rules() within
    wdl-ast/src/v1/validation.rs.
  • Lint rules added to wdl-ast should be added to fn rules() within wdl-ast/src/v1/lint.rs.
  • Validation rules added to wdl-grammar should be added to fn rules() within
    wdl-grammar/src/v1/validation.rs.
  • Lint rules added to wdl-grammar should be added to fn rules() within
    wdl-grammar/src/v1/lint.rs.
• You have added a test that covers every possible setting for the rule
  within the file where the rule is implemented.
• You have run wdl-gauntlet --save-config to ensure that all of the rules
  added/removed are now reflected in the baseline configuration file
  (Gauntlet.toml).

[a-frantz]

Should this be unreachable!()? When could something other than COMMENT or WHITESPACE be found before version?

[adthrasher]

I thought so, so I changed it. However, it broke a bunch of other tests.

[adthrasher]

It looks like the lints are being run as part of some of the other tests, e.g.

wdl/wdl-ast/src/v1/document/declaration/bound.rs

Line 186 in 35731ec

fn it_parses_from_a_supported_node_type() {

. Since those are testing individual nodes, there is no version declaration. I'm not sure if the lints should be running, I would have thought not. Maybe @claymcleod can weigh in.

[claymcleod]

I think, for individual tests, the lints can be disabled.

[adthrasher]

I'm not clear how they're being run (or how to disable, if that's what should happen). It's when I run cargo test --all-features, but it produces a long list of failures, most of which are it_parses_from_a_supported_node_type type tests.

    v1::document::declaration::bound::tests::it_parses_from_a_supported_node_type
    v1::document::declaration::unbound::tests::it_parses_from_a_supported_node_type
    v1::document::expression::array::tests::it_parses_from_a_supported_node_type
    v1::document::expression::map::tests::it_parses_from_a_supported_node_type
    v1::document::expression::pair::tests::it_parses_from_a_supported_node_type
    v1::document::expression::r#if::tests::it_parses_from_a_supported_node_type
    v1::document::expression::tests::ensure_number_works_correctly
    v1::document::expression::tests::it_correctly_parses_floats
    v1::document::expression::tests::it_ignores_comments_and_whitespace
    v1::document::identifier::qualified::tests::it_parses_from_a_supported_node_type
    v1::document::identifier::tests::it_parses_from_a_supported_node_type
    v1::document::import::tests::it_parses_a_complicated_import_correctly
    v1::document::output::builder::tests::it_parses_from_a_supported_node_type
    v1::document::private_declarations::tests::it_parses_from_a_supported_node_type
    v1::document::r#struct::tests::it_parses_from_a_supported_node_type
    v1::document::task::runtime::value::tests::it_correctly_parses_floats
    v1::document::task::runtime::value::tests::it_correctly_parses_integers
    v1::document::tests::it_parses_from_a_supported_node_type
    v1::document::workflow::execution::statement::call::body::tests::it_parses_from_a_supported_node_type
    v1::document::workflow::execution::statement::call::tests::it_parses_from_a_supported_node_type
    v1::document::workflow::execution::statement::conditional::tests::it_parses_from_a_supported_node_type
    v1::document::workflow::execution::statement::scatter::tests::it_parses_from_a_supported_node_type

[adthrasher]

Ah, I see. It's here in parse_rule.

wdl/wdl-grammar/src/v1.rs

Lines 177 to 179 in 35731ec

	if let Some(warnings) = Linter::lint(&pt, lint::rules()).map_err(Error::Lint)? {
	for warning in warnings {
	concerns = concerns.push(Concern::LintWarning(warning));

[adthrasher]

I don't see a way to disable running the lint rules in that function. It does appear that nothing is done with any lint warnings. Was this intentional?